1. Technical Field
The present invention relates generally to the field of data processing systems, and more specifically to a method, system, and computer program product for testing a memory system. Still more particularly, the present invention relates to a method, system, and computer program product for isolating a defect in a memory system by determining in which particular component of the memory system the defect exists.
2. Description of Related Art
Currently, in a minimum system configuration with a single memory extent, there is no reliable method in computer memory fault isolation techniques to isolate a hardware problem among a memory module, such as a dual inline memory module (DIMM), a memory controller, and a memory card, which is the device to which memory modules are attached. The known methods test all parts of the memory system coupled together. With all parts of the memory system coupled together, patterns of data are written using the data and address bits to the memory subsystem using the memory controller. Data is then read back from the memory subsystem using the memory controller. First the memory controller is tested. The logic around memory controller is then tested. The logic for memory card is tested next, and finally memory modules are tested. The pattern written to the memory system is then compared to the pattern read back from the memory system. If the patterns do not match, then it is determined that a defect exists within the memory system. However, all components of memory systems are tested as one single unit and cannot be tested individually. In addition to that, in the minimum configuration, when only one of each memory system component, such as memory controller, memory card, and memory module is present, any detected error may reside in any one of the interconnected elements and cannot be isolated.
This prior art method for determining if a defect exists in the memory system cannot test various components of memory system individually because the three components, the memory controller, memory card, and memory modules, are all tested together as a coupled unit. Further, in the case of the minimum configuration, the prior art method makes it difficult to identify exact which component is defective. Further to that, the prior art method also does not elaborately test the memory card component of memory system and the logic around it. As a result, in the case of a defective memory card component, the problem cannot be isolated to the defective memory component and may increase the number of field replacement units in order to correct the memory system errors.
Therefore, a need exists for a method, system, and product for isolating a defect in a memory system by determining in which particular component of the memory system the defect exists regardless of the system configuration and also provide the ability to test various memory system components individually without having a dependency among each other.